I do think Assange was biased in how/when he chose to use the information given to him during the 2016 US elections - but if political bias were a crime then every major US news network would have most of their journalists rounded up with Assange.
There is something much more vile at work here than journalistic bias or misconduct. We are watching fascism emerge, and learning that it doesn't slyly slither up, like a serpent before swiftly attacking its prey, no, it walks in the front door of our country, wipes it's feet on the welcome mat, is welcomed in with open arms and sits down to dinner with your family and friends.
The ideology behind protecting journalists, to use another apt metaphor, is the oil on the gears of democracy. Without that lubricant, that flow of critical information to the people, the machine inevitably grinds to a halt.
Metaphor and crafted phrases aside, no matter what your politics may be, or your opinion of Julian Assange, if you're a US citizen (or anyone that values democracy over fascism, really) then this should seem highly disturbing to you. This goes way beyond partisan issues, right to the core mechanism for maintaining a free society - freedom of press. The individuals who personally acquire the source material have always been the one's at risk, not the journalist or any other 3rd party who is merely sharing the information. This should not a debatable issue in a free or democratic society. The risk must be on those who would brave it in the name of doing what they feel is right, when they feel their duty to freedom outweighs duty to a government agency. Not to mention, the 'leak' on most people's minds from Assange is the 2016 Clinton material that Trump enthusiastically requested president Putin and his government obtain. But that is beside the fact, the main issue here is that even if you hate Assange and Wikileaks, we now have a precedent set that will discourage anyone from publishing any material that could save a democracy from digression to fascism. Likewise, the statement to already fascist states is that the USA no longer has the right (and likely not the desire) to take any action against those who lock up and murder journalists.
Freedom of the press, like all freedoms, requires that we allow some things to exist that we personally find distasteful. Allowing Assange the right to be protected under freedom of press, even if you dislike him or what he does, is one of those things you have to accept, or the system doesn't work. Freedom cannot be à la carte - it's an all you can eat buffet-style affair. Damnit, there I go with metaphor again...